EP0112452A2 - Catalytic preparation of nitroalkanes from alkanols - Google Patents
Catalytic preparation of nitroalkanes from alkanols Download PDFInfo
- Publication number
- EP0112452A2 EP0112452A2 EP83110434A EP83110434A EP0112452A2 EP 0112452 A2 EP0112452 A2 EP 0112452A2 EP 83110434 A EP83110434 A EP 83110434A EP 83110434 A EP83110434 A EP 83110434A EP 0112452 A2 EP0112452 A2 EP 0112452A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- catalyst
- temperature
- salt
- nitric acid
- oxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C201/00—Preparation of esters of nitric or nitrous acid or of compounds containing nitro or nitroso groups bound to a carbon skeleton
- C07C201/06—Preparation of nitro compounds
- C07C201/10—Preparation of nitro compounds by substitution of functional groups by nitro groups
Definitions
- Nitroalkanes are an essential stabilizing ingredient employed in 1,1,1-trichloroethane when it is used in vapor degreasing and cold cleaning. All manufacturers throughout the world add nitromethane and/or nitroethane to their commercial 1,1,1-trichloroethane- based solvents. Normally nitro-alkanes are manufactured by a vapor phase nitration of the alkane with either nitric acid or N0 2 . There is a mixture of products formed due to carbon-carbon scission. Thus, for example, when propane is nitrated, the products include 1-nitropropane, 2-nitropropane, nitroethane and nitromethane. Because of the oxidative conditions other oxygen containing compounds are also produced, e.g. aldehydes, acids and carbon oxides. Patents disclosing such a process are U.S. 2,844,634 and 2,905,724.
- Improvements in these vapor phase nitrations are claimed by employing the nitric acid or nitrogen oxides together with oxygenated sulfur compounds, e.g. S0 2 , H 2 SO 4 , (U.S. 3,272,874) and by conducting the nitration in the presence of ozone (U.S. 3,113,975).
- oxygenated sulfur compounds e.g. S0 2 , H 2 SO 4 , (U.S. 3,272,874) and by conducting the nitration in the presence of ozone (U.S. 3,113,975).
- the present invention is a departure from known methods in that it employs the reaction of an alkanol with nitric acid, or N0 2 gas, in the vapor phase over a catalyst.
- the catalyst is a salt or an oxide of a Group II metal, e.g. calcium or barium chloride, which may be supported or pelleted.
- a Group II metal e.g. calcium or barium chloride
- the process for manufacturing lower nitroalkanes, especially those containing 1-3 carbon atoms, according to the present invention involves a vaporization of a lower alkanol and nitric acid, mixing their vapors and passing over a catalyst which is a salt or oxide of a metal from Group II of the periodic table.
- the alkanol and nitric acid are conveniently pumped as liquids to individual vaporizers, mixed, and fed to a fixed bed catalyst over which they are transformed into nitromethane.
- An inert gas e.g. nitrogen, is preferably used as a diluent, and can be recycled.
- the vapors of the alkanol and nitric acid are thoroughly mixed, desirably in proportion of 10 to 1 noles of alkanol per mole of HN0 3 , preferably 4 to 2, and this mixture is preferably diluted with an inert gas, e.g. nitrogen, desirably at 2 to 15 moles of the inert iiluent per mole of alkanol.
- an inert gas e.g. nitrogen
- the preferred range is from about 4 to about 10 moles of diluent per mole of alkanol reactant.
- the diluent may be selected from inert gases including nitrogen, argon, the carbon oxides, steam and nixtures thereof.
- the gas mixture is preferably preheated to a temperature of from 100 to 250°C and the catalyst bed is preferably maintained at a temperature within the range of 150 to 350°C, more preferably from 210 to 260°C.
- the catalyst is a compound of metals of Group II of the periodic table, preferably magnesium, calcium, strontium and barium. Salts of these metals, including the chlorides, sulfates, and nitrates may be employed. The oxides of these metals are also useful as catalysts for the reaction. They may be employed separately or in combination. A preferred combination is CaCl 2 /BaCl 2 in a molar ratio of 1/4 to 4/1.
- Either the oxides or salts may be burdened on an inert support and used in this manner.
- Methods of making supported catalysts are well known to the art.
- the support may be impregnated by immersing it in a salt solution or by spraying the solution onto the support.
- a slurry is used in the case of oxides or insoluble salts.
- Pressures employed in the process are desirably from 1 to 150 psig (6.9 to 7130 kPa gauge) and preferably from 6 to 50 psig (41.4 to 345 kPa gauge).
- a catalyst was made for use in the following Examples by immersing an alumina support (a low surface area ( ⁇ 1 m 2 /g) spherical support of medium porosity manufactured by Norton and designated SA-5205) in an amount of aqueous CaCl 2 solution sufficient to completely wet it. Excess water was evaporated and the catalyst dried. The amount of CaCl 2 supplied was sufficient to provide a 21 percent by weight loading on the support. Portions were calcined under a nitrogen purge (oxygen excluded) at 150°C, 415°C, 500°C, 600°C, and 700°C each for a period of 4 hours.
- the different portions of the above prepared catalysts were run in a 4 foot by 3/4 inch (1220 mm by 19 mm) stainless steel tubular reactor system equipped with fluidized sand heat control, pressure and flow controllers, chilled water scrubber column, and an alarm system.
- a Brooks thermal mass controller was used to meter nitrogen flow.
- Milton Roy positive displacement pumps were used to meter the methanol and nitric acid flows.
- Methanol conversion differed only slightly, varying from 13 percent to 22 percent for the reaction run at 245°C, 5.5 sec contact time with a MeOH/HN0 3/ N 2 ratio of 4/1/24. Selectivity varied considerably for the reaction under the above conditions as is shown below in tabular form.
- the preferred method of preparing the catalyst is to calcine the salt or oxide of the metal on a support for a period of 2 to 10 hours at a temperature of from 500° to 700°C.
- a quantity (370 ml.) of a catalyst prepared according to the above description, calcined at 700°C for 4 hours and consisting of a 1/1 (atomic ratio of Ca/Ba) mixture of calcium chloride and barium chloride coated at 17.6 percent by weight on a low surface area alumina support (SA-5205) was loaded into the 4-foot (1220 mm) stainless steel tube reactor described above and heated to 270°C with a diluent gas (nitrogen) purging through the system.
- the pressure was controlled at 7 psig, preheater temperature 185°C, nitrogen flow 4000 cc/min., then nitric acid was started at 0.0076 gram mole/min. rate.
- Methanol was then started at 0.0301 gram mole/min. rate (4/1/24 CH 3 OH/HNO 3 /N 2 mole ratio).
- a supported catalyst containing CaCl 2/ Ca0 (1/1 mole ratio) was employed at different reactant ratios, contact times and temperatures to obtain the conversions and selectivities shown in Table I.
- the support was the same as employed in Examples 1 and 2 above and catalyst loading was 19.7 percent based on weight of the finished catalyst.
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Catalysts (AREA)
Abstract
Description
- Nitroalkanes are an essential stabilizing ingredient employed in 1,1,1-trichloroethane when it is used in vapor degreasing and cold cleaning. All manufacturers throughout the world add nitromethane and/or nitroethane to their commercial 1,1,1-trichloroethane- based solvents. Normally nitro-alkanes are manufactured by a vapor phase nitration of the alkane with either nitric acid or N02. There is a mixture of products formed due to carbon-carbon scission. Thus, for example, when propane is nitrated, the products include 1-nitropropane, 2-nitropropane, nitroethane and nitromethane. Because of the oxidative conditions other oxygen containing compounds are also produced, e.g. aldehydes, acids and carbon oxides. Patents disclosing such a process are U.S. 2,844,634 and 2,905,724.
- Improvements in these vapor phase nitrations are claimed by employing the nitric acid or nitrogen oxides together with oxygenated sulfur compounds, e.g. S02, H2SO4, (U.S. 3,272,874) and by conducting the nitration in the presence of ozone (U.S. 3,113,975).
- Other processes involve nitration of alkanes by nitrogen peroxide (N02)2 in the presence of oxygen (air) under pressure at 150°-330°C (U.S. 3,780,115); reacting an alkene with nitric acid in the presence of a lower aliphatic monocarboxylic acid anhydride to produce a nitroester, subsequently reducing it with an alkali borohydride to form the nitroalkane (U.S. 3,706,808) and reacting organic amines with ozone (U.S. 3,377,387).
- The present invention is a departure from known methods in that it employs the reaction of an alkanol with nitric acid, or N02 gas, in the vapor phase over a catalyst.
- The catalyst is a salt or an oxide of a Group II metal, e.g. calcium or barium chloride, which may be supported or pelleted.
- The process for manufacturing lower nitroalkanes, especially those containing 1-3 carbon atoms, according to the present invention involves a vaporization of a lower alkanol and nitric acid, mixing their vapors and passing over a catalyst which is a salt or oxide of a metal from Group II of the periodic table. The alkanol and nitric acid are conveniently pumped as liquids to individual vaporizers, mixed, and fed to a fixed bed catalyst over which they are transformed into nitromethane. An inert gas, e.g. nitrogen, is preferably used as a diluent, and can be recycled.
- The vapors of the alkanol and nitric acid are thoroughly mixed, desirably in proportion of 10 to 1 noles of alkanol per mole of HN03, preferably 4 to 2, and this mixture is preferably diluted with an inert gas, e.g. nitrogen, desirably at 2 to 15 moles of the inert iiluent per mole of alkanol. The preferred range is from about 4 to about 10 moles of diluent per mole of alkanol reactant. The diluent may be selected from inert gases including nitrogen, argon, the carbon oxides, steam and nixtures thereof.
- The gas mixture is preferably preheated to a temperature of from 100 to 250°C and the catalyst bed is preferably maintained at a temperature within the range of 150 to 350°C, more preferably from 210 to 260°C.
- The catalyst is a compound of metals of Group II of the periodic table, preferably magnesium, calcium, strontium and barium. Salts of these metals, including the chlorides, sulfates, and nitrates may be employed. The oxides of these metals are also useful as catalysts for the reaction. They may be employed separately or in combination. A preferred combination is CaCl2/BaCl2 in a molar ratio of 1/4 to 4/1.
- Either the oxides or salts may be burdened on an inert support and used in this manner. Methods of making supported catalysts are well known to the art. For example, the support may be impregnated by immersing it in a salt solution or by spraying the solution onto the support. A slurry is used in the case of oxides or insoluble salts.
- Pressures employed in the process are desirably from 1 to 150 psig (6.9 to 7130 kPa gauge) and preferably from 6 to 50 psig (41.4 to 345 kPa gauge).
- A catalyst was made for use in the following Examples by immersing an alumina support (a low surface area (<1 m2/g) spherical support of medium porosity manufactured by Norton and designated SA-5205) in an amount of aqueous CaCl2 solution sufficient to completely wet it. Excess water was evaporated and the catalyst dried. The amount of CaCl2 supplied was sufficient to provide a 21 percent by weight loading on the support. Portions were calcined under a nitrogen purge (oxygen excluded) at 150°C, 415°C, 500°C, 600°C, and 700°C each for a period of 4 hours.
- The different portions of the above prepared catalysts were run in a 4 foot by 3/4 inch (1220 mm by 19 mm) stainless steel tubular reactor system equipped with fluidized sand heat control, pressure and flow controllers, chilled water scrubber column, and an alarm system. A Brooks thermal mass controller was used to meter nitrogen flow. Milton Roy positive displacement pumps were used to meter the methanol and nitric acid flows. Methanol conversion differed only slightly, varying from 13 percent to 22 percent for the reaction run at 245°C, 5.5 sec contact time with a MeOH/HN03/N2 ratio of 4/1/24. Selectivity varied considerably for the reaction under the above conditions as is shown below in tabular form.
- A quantity (370 ml.) of a catalyst prepared according to the above description, calcined at 700°C for 4 hours and consisting of a 1/1 (atomic ratio of Ca/Ba) mixture of calcium chloride and barium chloride coated at 17.6 percent by weight on a low surface area alumina support (SA-5205) was loaded into the 4-foot (1220 mm) stainless steel tube reactor described above and heated to 270°C with a diluent gas (nitrogen) purging through the system. The pressure was controlled at 7 psig, preheater temperature 185°C, nitrogen flow 4000 cc/min., then nitric acid was started at 0.0076 gram mole/min. rate. Methanol was then started at 0.0301 gram mole/min. rate (4/1/24 CH3OH/HNO3/N2 mole ratio).
- Analysis of the condensed reactor effluent showed a 17 percent conversion of methanol and a 60 percent selectivity to nitromethane.
- A supported catalyst containing CaCl2/Ca0 (1/1 mole ratio) was employed at different reactant ratios, contact times and temperatures to obtain the conversions and selectivities shown in Table I. The support was the same as employed in Examples 1 and 2 above and catalyst loading was 19.7 percent based on weight of the finished catalyst.
-
- Other Group II metals were tested in a 1-foot by 1 inch (305 mm x 25.4 mm) stainless steel tubular reactor equipped as the longer reactor. Conditions under which the reaction was run were preheater temperature 185°C, nitrogen flow 4000 ml/min. and pressure 7 psig. Table III shows the reaction parameters and results:
- A catalyst of 16 percent CaCl2 on alumina spheres, calcined at 700°C for 4 hours, employed in the 4-foot (1220 mm) reactor at various temperatures, was run at a MeOH/HN03/N2 ratio of 3.8/1/24, 4 sec. contact time and a pressure of 8 psig. A quantity of 370 ml of catalyst was employed as in Example 1. Results are shown in Table IV.
Claims (13)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/446,076 US4431842A (en) | 1982-12-01 | 1982-12-01 | Catalytic preparation of nitroalkanes |
US446076 | 1982-12-01 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0112452A2 true EP0112452A2 (en) | 1984-07-04 |
EP0112452A3 EP0112452A3 (en) | 1985-09-18 |
EP0112452B1 EP0112452B1 (en) | 1987-12-16 |
Family
ID=23771238
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP83110434A Expired EP0112452B1 (en) | 1982-12-01 | 1983-10-19 | Catalytic preparation of nitroalkanes from alkanols |
Country Status (11)
Country | Link |
---|---|
US (1) | US4431842A (en) |
EP (1) | EP0112452B1 (en) |
JP (1) | JPS59110654A (en) |
AU (1) | AU561023B2 (en) |
BR (1) | BR8304730A (en) |
CA (1) | CA1203814A (en) |
DE (1) | DE3374931D1 (en) |
DK (1) | DK156389C (en) |
ES (1) | ES8505638A1 (en) |
NO (1) | NO158095C (en) |
ZA (1) | ZA835805B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013025061A2 (en) * | 2011-08-17 | 2013-02-21 | 한국화학연구원 | Method for preparing nitroparaffin by gas phase nitration |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA1244836A (en) * | 1984-03-14 | 1988-11-15 | Teruyuki Nagata | Process for producing diphenylamines or n,n'-diphenyl- phenylenediamines |
FR2632635B1 (en) * | 1988-06-09 | 1990-10-19 | Seppic Sa | PROCESS FOR THE MANUFACTURE OF NITROMETHANE |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3957889A (en) * | 1975-05-02 | 1976-05-18 | Air Products And Chemicals, Inc. | Selective nitration of aromatic and substituted aromatic compositions |
US4122124A (en) * | 1977-12-05 | 1978-10-24 | Rockwell International Corporation | Production of trinitromethane |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB578044A (en) * | 1943-04-23 | 1946-06-13 | Malcolm Percival Appleby | Improvements in and relating to the production of nitroparaffins |
NL125045C (en) * | 1959-10-28 |
-
1982
- 1982-12-01 US US06/446,076 patent/US4431842A/en not_active Expired - Fee Related
-
1983
- 1983-08-05 CA CA000433982A patent/CA1203814A/en not_active Expired
- 1983-08-08 AU AU17677/83A patent/AU561023B2/en not_active Ceased
- 1983-08-08 ZA ZA835805A patent/ZA835805B/en unknown
- 1983-08-11 ES ES524883A patent/ES8505638A1/en not_active Expired
- 1983-08-26 BR BR8304730A patent/BR8304730A/en not_active IP Right Cessation
- 1983-09-01 NO NO833130A patent/NO158095C/en unknown
- 1983-10-19 EP EP83110434A patent/EP0112452B1/en not_active Expired
- 1983-10-19 DE DE8383110434T patent/DE3374931D1/en not_active Expired
- 1983-10-28 DK DK496183A patent/DK156389C/en active
- 1983-12-01 JP JP58225536A patent/JPS59110654A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3957889A (en) * | 1975-05-02 | 1976-05-18 | Air Products And Chemicals, Inc. | Selective nitration of aromatic and substituted aromatic compositions |
US4122124A (en) * | 1977-12-05 | 1978-10-24 | Rockwell International Corporation | Production of trinitromethane |
Non-Patent Citations (1)
Title |
---|
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, vol. 76, no. 10, 26th May 1954, pages 2692-2694; H.B.HASS et al.: "Vapor phase nitration of aliphatic ethers, alcohols, ketones and carboxylic acids" * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013025061A2 (en) * | 2011-08-17 | 2013-02-21 | 한국화학연구원 | Method for preparing nitroparaffin by gas phase nitration |
WO2013025061A3 (en) * | 2011-08-17 | 2013-05-30 | 한국화학연구원 | Method for preparing nitroparaffin by gas phase nitration |
Also Published As
Publication number | Publication date |
---|---|
DK496183A (en) | 1984-06-02 |
CA1203814A (en) | 1986-04-29 |
NO833130L (en) | 1984-06-04 |
ES524883A0 (en) | 1985-06-01 |
BR8304730A (en) | 1984-11-06 |
EP0112452A3 (en) | 1985-09-18 |
NO158095C (en) | 1988-07-13 |
AU1767783A (en) | 1984-06-07 |
DK156389B (en) | 1989-08-14 |
EP0112452B1 (en) | 1987-12-16 |
ES8505638A1 (en) | 1985-06-01 |
JPS59110654A (en) | 1984-06-26 |
AU561023B2 (en) | 1987-04-30 |
DK496183D0 (en) | 1983-10-28 |
ZA835805B (en) | 1985-03-27 |
DK156389C (en) | 1990-01-08 |
US4431842A (en) | 1984-02-14 |
NO158095B (en) | 1988-04-05 |
DE3374931D1 (en) | 1988-01-28 |
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